A handheld suction cleaner is compact, cordless, and thus applicable to vehicles or in other places where no power jack is configured. However, the handheld suction cleaner is powered by a rechargeable battery, and the running time of the charged handheld suction cleaner soon begins to decline. In most cases, a conventional handheld suction cleaner can merely work for approximately ten minutes or more. Thereafter, the handheld suction cleaner is less capable of collecting dust due to insufficient power supply. Besides, the conventional handheld suction cleaner does not have intelligent functions. In other words, after the conventional handheld suction cleaner is turned on, it rotates at a single rotation rate, and the suction force and the rotation rate of the conventional handheld suction cleaner cannot be spontaneously adjusted based on the operating condition of the suction cleaner or the amount of dust collected by the suction cleaner.
Generally, after the handheld suction cleaner is turned on, the handheld suction cleaner collects dust at a constantly high rotation speed, and the limited running time of the charged handheld suction cleaner results from the significant power consumption of the suction cleaner operating at the high rotation speed. Even though the user has not yet started the dust-suction process, or the suction cleaner is not in contact with dust particles or debris, the suction cleaner in operation constantly generates a strong suction airflow, and thus the power stored in the rechargeable battery continues to be consumed. This reduces the running time of the charged suction cleaner.